The strongest yakuza in all of Japan and the next in line to take over the famous Kantou Sharp Fang Mafia Organization is a complete idiot??? 27 year old Sakaki Makio has screwed up once again and failed the 'organization'. His father and existing boss declares that unless he graduates high school he will not be allowed to take over the gang. Under the guise of a 17 year old transfer student, Makio enters high school. This drama follows his comical situation as he balances being the toughest mafia boss on block while acting like a normal high school senior.